Answer: You should check whether the encounter qualifies for time-based billing. If the FP spent the majority of the visit on counseling, you can use time as the key element.
Example: An FP spends five minutes examining a patient and 10 minutes counseling the patient prior to diagnosing the patient with depression. Because counseling dominated the encounter, you can report 99213 based on time (Office or other outpatient visit for the evaluation and management of an established patient ... physicians typically spend 15 minutes face-to-face with the patient and/or family ...). Link the appropriate ICD-9 code, such as 311 (Depressive disorder, not elsewhere classified), to 99213.
Tip: The FP should document the visit's total time (T), counseling (C) time, and discussion content, such as 15T/10C "depression." Doing so will alert you to the fact that the FP is billing based on time, and will help you fight any downcoding challenges.